html,body{
  overflow:hidden;
}

#demo{
  text-align:center;
  display: flex;
  justify-content: center;
  background-image:url(uranai.png);
  background-size:cover;
  background-position:50%;

}

h2{
  font-size:32px;
  color:#ff0000;
  padding-top:20px;
  padding-bottom:10px;
}
button{
  display:inline-block;
  border-radius:20px;
  margin:40px;
}
select,button{
  font-size:64px;
}

form,#result{
  width:460px;
  height:580px;
  margin:40px auto;
  padding:10px;
  border-radius:20px;
  background-color:rgba(0,0,0,0.8);
  color:#ffffff;
}
#sign{
  font-size:80px;
}
form img{
  width:80px;
  animation:3s linear infinite rotation;
}
@keyframes rotation{
  0%{ transform:rotate(0);}
  100%{ transform:rotate(360deg); }
}